LXXXIX, GRAMINEA., 507 
Spike cylindrical or slightly interrupted. Flowering gaia white and mem- 
42 branous ; 40. K®LERIA. 
Clusters one- sided, in an irr eoular spike or close panicle. "Glumes herbaceous 
and rigid é i : P . 2% DACTYLIS. 
43 Outer olumes enclosing the flowers or nearly BOM: ; : : ; 5 . 44 
eOnters glumes shorter than the flowers . 45 
Glumes obtuse, coloured. ‘Two flowers with a wedge- shaped rudimentary 
glume . 38. MELICA. 
44 Outer glumes very acute. About 3 flowers in the spikelet, all perfect, with 3- 
toothed glumes. : 39. TRIODIA. 
Glumes all acute. Two male flowers and 1 smaller perfect one in the spikelet. 
4, HTEROCHLOF. 
First outer glume very small, second broadly truncate at the top, and often 
45 coloured. Flowers 2 in the spikelet . i” BB. ean 
core Shatag glumes pointed or obtuse, not truncate. Flowers usually 3 
46 
Spikelets broadly ovate or orbicular. Glumes closely packed and very spread- 
4 | ing. 2 : , . F : . 84 BRIZA. 
Spikelets oblong orlinear . ; ; é - 47 
47 { Flowering glumes rounded on the back, atleast at the base. ; . 48 
Flowering elumes keeled on the back . : : ; : ‘ : 49 
48 Flowering glumes obtuse or rather acute . : 2 . eld. 35. Poa. 
Flowering glumes very pointed or shortly awned 31. FESTUCA. 
Flowering glumes very pointed. Flowers about 3, with a br istle- like continua- 
so} tion of the axil . ; 37. MOLINIA. 
Flowering glumes obtuse or acute, Flowers 3 or more, the last terminal 35. Poa. 
The limits of the numerous genera into which Grasses are divided are 
as yet far from being definitely fixed. Some are by no means natural, 
and those which are so have not always any definite characters. They 
have also been variously distributed into tribes, according to the special 
views of their structure entertained by different botanists. Amongst 
those which appeared to be the most generally adopted, eight tribes 
were, in the first editions of this work, distinguished as being re- 
presented in Britain. Since then a detailed study of a considerable 
part of the Order, in connection with the Australian Flora, has sug- 
gested some modifications in the general grouping of the genera, but 
as the new tribes cannot yet be considered as definitely settled, the 
sequence adopted in the first edition is here left undisturbed. A general 
sketch, however, of the proposed arrangement as affecting British 
genera is now added, observing at the same time that here and there 
an exceptional species may not be in strict conformity with the tribal 
character; but fewer, it is believed, than in the case of any other 
method hitherto proposed. 
* Pedicel articulate below the outer gluines. Spikelet with 1 terminal fertile flower, 
the male or barren flower (if any) or empty glumes below it. (PANICACE.) 
1. PANICEH. Flowering glume of a firmer texture than the empty ones below 
it :—3. PANICUM. 
2. ANDROPOGONES%. Flowering glume much thinner and smaller than the empty 
one below it, and often bearing a twisted awn :—12. POLYPOGON. 
The above two tribes, so sparingly represented in Britain, comprise a very large 
proportion of tropical GRAMINE®. 
** Articulation, when present, under the flowering glumes, but above the two outer 
ones. Spikelets with one ov more flowers and frequently a male flower or empty 
glume above them, the male flower rarely. below them. (POACER.) 
3. PHALARIDE%. Glumes normally 6, 2 below the articulation, 2 immediately 
above it, usually small and empty or with a male flower in each, 2 upper nearly 
equal, enclosing a single perfect flower. No true palea (the lower glumes oc¢a- 
sionally deficient) :—1l. LEERSIA; 9. ALOPECURUS; 6. PHALARIS; 7. DIGRAPHIS; 
5. ANTHOXANTHUM; 4. HIEROCHLOE. 
4, STREPTATHER®. Spikelets with 1, 2, or rarely more perfect flowers. Flowering 
